Controlling combustion



F. +1. BRowN CONTROLLING COMBUSTION July 24I1923. 1,463,143

Original Filed March 28 1917 5 Sheets-She'et l F.=H. BRbwN CONT-ROLLING COMBUSTION July 24,, 19213.

Original Filed March 28 1917 3 Sheets-sheet 2 \NVENTOR July 24, 192?.- 1,463,143

- F. H. BROWN CONTROLLING COMBUSTION Original Filed March 28 1917 3 Sheets-Sheet 5 Patented July 24-, 1923.

ea iii Farmers rr. Baown', or arDLEY PARK,

;i'r rice.

rnnnsvnvaura, assreuon, Bi'z A CORPORATION OF FENHSYLVANIA.

cournonnine COMBUSTION.

filed March 23, 1917, Serial Il'o. 1922. Serial Original application To all whom it may concern.

Be it known that 1, Francis H. BROWN, residing at Ridley Park in the county 'of Delaware and State of Pennsylvania, a c1t1- 5 zen of the United States, have invented or discovered certain new and useful Improvements in Controlling Combustion, of which improvements the following is a specificat on.

The invention described in this application is a ,divisionof an application Serial Number 157 filed by me hla'r'ch 28, 1917, consisting of a combination of mechanisms for controlling combustion, a prominent feature of which is the automatic control of the fuel feed by means of mechanism regulated by and in accordance with variations of pres sure in the furnace posterior to the bed of f el- The invention istlesign'e'd to be ut lized in conjunction with any desired type of furnace and in conjunction with any desired type of fuel, as forexample, S Olll ll'qll lCl, or gaseous fuel, so that the introduction or such fuel to the pointof combustion will be accuratelv controlled in accordance with the varying conditions which are taking place 111 the furnace. I I

A further purpose of this invention 1s to utilize in conjunction with the automatic control of the fuel feed, mechanism as for example, a stoker or its equivalent means for automatically varying the furnace pressure in accordance with the variation in load on the furnace. This load varies in character in accordance with the character of the furnace employed and in a boiler furnace the load would be the variation in the demand for steam while in a heating furnace it might be the variation in heat within the furnace.

For the purpose of illustrating my invention I have shown in the accompanying drawings typical embodiments of it which are at present preferred by me since these embodiments will give in practice satisfactory and reliable results although it is to understood that the various instrumentalities of which the invention consists and by means of which my method can be carried out, can be variously arranged and organized and that my invention is not limited to a precise arrangement and organization of 157,921. Divided aid this aptneaaba fiiea June 21,

No. teases;

these instrumentalities as herein shown and described. v

v Fig; 1 represents iii sectional elevation one type of a furnace having embodied therewith my improvementsin controlling mechanism, Fig. 2 represents in side elevation on an enlarged scale automatic regulating device seen in Fig. 1'; shows in sectional elevation thecontrolling valve seen in' Fig. 4;; Fig. 4: shows partly in section and partly in elevation the pressure regulator seen in Fig. 1'; Fig. '5 shows in side elevation another embodiment of my inventionillustrating a different type of fuel feeding mechanism for feeding liquid or gaseous fuel; Fig. 6 shows section on line VL-VI Fig. 2; and F ig. 7 is a View similar to Fig. 1 illustrating another embodiment of my invention.

It is to be understood in carrying out my novel method in practice that I do not desire to be limited to any special type of stoker or fuel feeding mechanism, to any special type of regulator controlled by the variation in load on the furnace, to any special type of a regulator controlled by varying conditions posterior to the point of combustion, such asfor example, a pressure regulator, or to the steps of utilizing natural, or mechanical draft or any special type of mechanism for controlling forced draft.

1 designates a furnace of any desired or conventionaltype, and as illustrated in the drawings, it is indicative of one. of the individual furnaces of a battery of boilers for the generation of steam so that the load on each furnace is the variation in steam demand; 2 designates the ash pit and 3 the fuel feeding mechanism which is intended to disclose the equivalent of a sto-ker, and consists in a travelling grate, the movement of which is controlled by an engine 1,0f any desired or conventional type and which is illustrated diagramatically in Figure 1. It will be understood that the engine 1 is operatively connected with the travelling grate 3 in order to impart movement thereto.

5 designates a combustion chamber which is in communication with the individual stack 6, through which the products of combustion pass to the main furnace stack 7. 8 designates a boiler, in which the steam is generated, and from which it is conducted through the dome v9 to any desired point of utilization. 10 designates a pressure regulator of the type which is now well known in the art and-which may be constructed substantially in accordance with one of my prior and has its free end extending above the 'l1qu1d in a contamer 12 and into the chamber 13 of an inverted tank 14. This tank 14 is located within the outer inverted tank 13 and these tanks have their lower ends sealed by the liquid in the container 12. The inverted tanks 14 and 15 are carried at one end of a lever 16 fulcrumed in any desired manner and provided with an adjustable counterbalance 17. It will be understood that the buoyant action of the liquid in which the inverted tanks 14 and 15 are submerged will be lessened as the tanks are moved upward and the force of gravity will supplement the atmospheric pressure on the tanks to retard the upward movement of the tanks, and this gravital action will increase in proportion to the upward movement of the tanks.

18' designates a. link which is connected with a valve 19 which controls admission and discharge of motive fluid through the pipes 20 and 21 to opposite ends of a motor chamber 22, and inwhich is located a reciprocatory piston 23. 24 designates a piston rod, the lower end of which is connected with a lever 25, which is .fulc'rumed on one end of a link 26, the other end of which is pivotally carried bythe frame or housing of the pressure regulator. The free end of the lever 25 is pivotally connected With a valve stem 27 to which is connected a valve 28 having a port 29 through its side wall. This valve 28 is illustrated as a cup-shaped valve slidable in a valve casing 30 which is provided with an inlet 31 and an outlet 32. The inlet communicates by means of a port 33 with the interior of the valve casing 30 and theport 29 registers at times with the port 33. The valve 28 is shown as a cup shaped valve having the ports 34 through one end to balance the pressure of motive fluid against the valve. The inlet 31 communicates by means of a valve controlled conduit with the steam dome 9. The outlet 32 communicates by means of a valve controlled conduit36 with the engine 4. The piston rod 24 of the pressure regulator 10 has connected to its upper end a cable 37 which passes over pulleys 38 and is connected to a damper 39 in the auxiliary draft conduit 40 which communicates with the ash-pit 2. The damper 39 is provided with an adjustable counterbalance 41. The auxthe main draft conduit 42 which is in communication with each furnace of the battery. The furnace may be operated under either a natural or forced draft and I have illustrated in Figure 1 a draft conduit 43 for the natural draft so that when the damper 44 is closed, thev furnaces will operate under natural draft. When the damper 44 is opened, as indicated in dotted lines in Figure 1, theblower 45 is in communication with the main draft conduit 42 so that the furnaces will operate under forced draft. The blower 45 is intended to illustrate the conventional type of forced draft wherein the blower is actuated by an'engine 46 which is provided with a. governor 47, so that the speed the engine can be automatically controlled.

Each individual stack 6is provided with a damper 48 having a counterbalance 49'and provided with a cable 50 which extends into a position accessible to the engineer in order to provide for the manual control of the damper 48. Each individual stack 6 is provided with an automatically controlled damper 51 which is provided with a pulley 52 around which passes a cable 53, which is The lever 61 is provided actuated by diaphragm motor 64 of any conventional type, one side of which is sub jected to variations in steam pressure which is introduced into proximity to said diaphragm through a steam conduit 65 which is in communication with the steam dome 9. The lever 59is connected by means of a link 66 with an elbow lever 67 which is fulcruined to a fixed point. This elbow lever 67 carries at one end a shoe 68 which is slid ably mounted upon a guide 69 pivoted at its lower end to a fixed point as 70, on a bracket 71 which is adjustably fixed to the piston rod 58 which is connected to the cable 53. The upper end of the bracket 71 is provided with a worm 72 adapted to be manually adj usted and which meshes With a rack 73 at the upper end of the guide 69 in order to provide for the angular adjustment of the said guide 69. This bracket 71 and its adjuncts form a compensating mechanism, so that a graduated adjustment of the damper 51 i automatically provided in accordance with variations in the steam pressure.

It will be'seen from Figure 6 that the shoe asal-asliquid or gaseous fuel is used. The cable 37' in Figure 5 would be connected to the pressure regulator 10 and controls the auxiliary draft conduit a0 to the individual furnace in the same manner as already described with reference to Figure 1, and I have therefore identified the corresponding" parts by the same reference characters. Connected to the cable 37 is a cable 74- which passes around a controlling valve and is pro-- vided with a counterbalance 76. The valve 75 automatically controls the passage of fuel of a liquid or gaseous nature through the nozzle or inje :tor 7'7. The-other parts of the mechanism for controlling combustion would correspond to the typical mechanism illustrated in Fig. 1. r

The operation of my novel apparatus will now be readily understood by and apparent to'those skilled in the art to which this invention appertains and is as follows The furnace can be operated under either natural or forced draft, and the mechanism for producing theforced draft is preferably automatically regulated. As the demand for steam increases, or in other words, the load on the individual furnace, the diaphragm motor 64 isactuated to control-the pilot valve 57 to thereby admit motive fluid to the motor 56 tocause the damper 51 to move in the direction of opening and thereby decrease the pressure posterior to the point of combustion, such for example as the furnace pressure in the combustion chamber since such combustion chamber is now in communicatlon wlth the atmosphere through the stack 6 of the individual fur-' nace. This change in pressure causes the lever 16 to be actuated to operate the pilot valve 19 and admit motive fluid to the motor 22 and thereby actuate the piston rod 24. The

piston rod 24 will move downwardly thereby causing the lever 25 to move the valve stem" 27 upwardly, and steam is permitted to pass from the conduit 35 through the inlet 31, the ports 38 and 29, through the port 82 into the conduit 36 and thence .to the engine 1 tocause the fuel to be fed into the furnace. This downward movement of the piston rod 24 actuates the cable 37 to open the valve 39 and permit the draft for combustion to pass from the main draft conduit 42 into the ash-pit 2 of the individual boiler.

In order to illustrate the onemanner of carrying out my method, I have preferred to show a single instrumentality for simul taneously controlling the operation of the fuel feeding 'mechanismand the introduc tion of' draftfor combustion, but'itis to be understood that it is-with-in the scope of my invention to employ separate mechanisms for sucli'control in accordance with conditions and requirementsmet with in practice.

hen the loadon the furnace decreases, 1

suchfor example, adecrease in the demandfor steamythe'motor 56 willbe 'actuated to causethedamper 51' to close to a degree corresponding to the change in steam pressure,

and the fuel'feeding mechanism and the primary draft'will' be correspondingly actuated to decrease'the amount of fuel being fed and the amount of air introduced for combustion. Owing to the provision of the compensating mechanism which is best 'illiistrat'edin Figures-2 and 6, the damper51 is not moved to a fully open or closed position on the variation in steam pressure but a graduated movement isprovided. The bracket 71, carri-ed-bythe piston rod 55, as it moves in'onedirection or the other, actuates the shoe 68 to move the valvestem 58 and correspondingly control the pilot valve 57; His not essential in all cases arising, inpractice to use all. of thesteps ofjmy method asherein set forth and they can be used alone and independently of each other or in any combination. 7

In so far as I am aware, I am the first'in the artto devise the'step of automatically; controllingv the fuel feed'by variations in furnace conditionspos'terior to thepoint of combustion; such'as forezrample, the variations in the furnace pressure. I amalsothe first in the art, in so far as I'amaware, to employ in conjunction with such step, the automatic control of the primary draft in accordance with varying conditions posterior to the point of combustion, either alone or in conjunction with the step of automatically varyingconditions posterior to the point of combustion in accordance. with variations in load on the furnace or furnaces. It istherefore to be understood that my claims to such" features areto be interpreted with the scope to which a generic invention is entitled.

1- In some cases arising in practice, the damper 51' and its adjuncts may be dispensed with and the damper 48 can be manu ally controlled to vary the conditions ofpressure posterior to the point of combustion I Another embodiment of my invention is seen in Fig. 7 wherein instead of controlling the damper 51 by variations in steam pressure, it is controlled by variations in furnace conditions posterior to'the'pointof com bustion, such as for example, the furnace pressure In this embodiment, the steam regulator seen in, Fig.1 2 is dispensedfwith, and the cable 37"is'conn'ected to or forms'a part of the cable ,53 which controlsth'e statement of the invention and tne 30 fuel. It is to be understood that in conjimction with this embodiment seen in Fig. 7, f dispense with the damper 39 and its automatlc control, and the engine is automat1- 'cally controlled by steam passing from the dome 9 through the conduit 78, the by-pass 7 9 and the steam regulating valve 80, the

valve 81 being closed and the valves 82 opened and the governor being disconnect ed. In the method first described in connection with Figure l the valve 82 would be closed and the valve 81 would be open. In accordance with my present invention, one is enabled to maintain a constant rate of combustion in each furnace, irrespective of the thickness of the bed of fuel or the resistance offered to the draft.

It will nowbe apparent that I have devised a new and useful method of controlling combustion, which embodies the features of advantage enumerated as desirable in the 1 above description, and While I have, in the present instance, shown and described typical embodiments thereofwhich will give in practice satisfactory and reliable results, it is to be understood that these embodiments are susceptible of modification invarious particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

1 claim herein as my invention:

'1. The method of controlling combustion in a furnace which consists in automatically controlling the source of supply of the forced draft for combustion, and automatically controlling the fuel feed and the discharge of products of combustion from the furnace by variations in furnace conditions posterior to the point of combustion.

2. The method of controlling combustion in a furnace which consists in' automatically controlling the source of supply of a forced draftfor combustion, and automatically controlling the fuel feed and the discharge of products of combustion from the. furnace by variations in furnace pressure.

3. The method of regulating furnaces which consists in maintaining in the furnace chamber a substantially uniform pressure under varying rates of combustion, and in regulatin'gthe resistance of the fuel bed tobear any desired relation to the rate of combustion by controllingthe rate of feed of fuel in accordance with variations in the means for maintaining in the furnace a substantially uniform pressure.

f. The method ofregulating furnaces which consists in maintaining in the furnace chamber a substantially uniform pressure under varying ratesof combustion and .in automatically regulating the resistance of the fuel bed to bear any desired relation to the rate of combust on by controlling the rate of feed. of fuel in accordance with variations in the means for maintaining in the furnace a substantially uniform pressure.

5. The method of regulating furnaces which consists in maintaining in the. furnace chamber a substantiallyuniform pres sure unoer varying rates of combustion, and in regulatlng the resistancev of the fuel bed to correspond to different ofconibi'istion by controlling the rate of feed of fuel in accordance with variations in said ineansfor maintaining. in the furnace a substantially uniform pressure.

6. The method of regulating furnaces which consists in maintaining in the furnace chamber a substantially uni-form pressure under varying rates of combustion, and in. automatically regulating the resistance of the fuelbed to correspond to different rates of combustion bycontrolling the rate of feed said of fuel in accordance with variations in submeans for maintaining in the furnace a staniially" uniform pressure.

. '2'. The method of regulatii'ig, furnaces,

which consists in maintaining in the; furnace chamber a substantially uniform pressure under varying rates of combustion and n regulating'the rate of feed of fuel in cordance with variations inthe means for maintain ng 1n the furnace a substant ally uniform pressure, and in such manner that the rate of feed of fuel will vary inversely furnaces bed resistance to rate-of supply, and directly as to the rate of air supply.

9. The method of regulating furnaces which consists in maintaining in the furnace chamber a substantially uniform pressure under varying rates of combustion, and in regulating the rate of feedyof fuel in ac-'- cordance with variations inthemcans for maintaining uniform pressure under varying rates of combustion so that the rate of feed of fuel will vary inversely as the resistance. as the rate of of the fuel bed, and directly supply ofair to the furnace.

10. The method of regulating furnaces which consists in maintaining in the furnace chamber a substantially uniform pressure under varying rates of combustion, and in automatically regulating the rate of feed of fuel in accordance with variations in the means for maintaining uniform pressure under varying rates of combustion, so that the rate of feed of fuel will vary inversely as the resistance of the fuel bed, and directly as the rate of supply of air to the furnace.

11. The method of operating boiler furnaces which consists in maintaining a sub stantially uniform furnace gas pressure for varying rates of combustion and regulating the rate of fuel feed in accordance with the rate of outflow of the furnace gases.

12. A boiler furnace having in combination therewith air mpelling means for supplying draft thereto, a stoker for feeding fuelto the furnace regulating means for maintaining the pressure of the furnace gases substantially uniform for varying rates of combustion, and means whereby the stoker is controlled by said regulatingmeans.

l3. A boiler furnace having in combination therewith means for feeding fuel thereto, regulating means for maintaining the pressure of the furnacegases substantially uniform for varying rates of combustion,

and means whereby the fuel feeding means is controlled by said regulating means.

14. A boiler furnace having in combination therewith air impelling means for supplying draft thereto, a stoker for feeding fuel to the furnace, regulating means for maintaining the pressure of furnace gases for the furnace controlled by said regulator.

16. A furnace having in combination therewith a stoker for feeding fuel thereto, air impelling means for furnishing draft, means for controlling the air impelling means by the steam pressure of the boiler, means for controlling the stoker in accord ance with the variations of the air impelling means, and means for maintaining substantially uniform pressure in the furnace for varying rates of combustion which last named means also varies the relative speed of the stoker to that of the air impelling means.

In testimony whereof, I have hereunto set my hand.

Q FRANCIS H. BROWN. 

